Riordan numbers: Difference between revisions
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#":(1e4-1){riordanext^:(1e4) x:1 0
4765</syntaxhighlight>
=={{header|Java}}==
<syntaxhighlight lang="java">
import java.math.BigInteger;
import java.util.List;
public final class RiordanNumbers {
public static void main(String[] args) {
final int limit = 10_000;
final BigInteger THREE = BigInteger.valueOf(3);
BigInteger[] riordans = new BigInteger[limit];
riordans[0] = BigInteger.ONE;
riordans[1] = BigInteger.ZERO;
for ( int n = 2; n < limit; n++ ) {
BigInteger term = BigInteger.TWO.multiply(riordans[n - 1]).add(THREE.multiply(riordans[n - 2]));
riordans[n] = BigInteger.valueOf(n - 1).multiply(term).divide(BigInteger.valueOf(n + 1));
}
System.out.println("The first 32 Riordan numbers:");
for ( int i = 0; i < 32; i++ ) {
System.out.print(String.format("%14d%s", riordans[i], ( i % 4 == 3 ? "\n" :" " )));
}
System.out.println();
for ( int count : List.of( 1_000, 10_000 ) ) {
int length = riordans[count - 1].toString().length();
System.out.println("The " + count + "th Riordan number has " + length + " digits");
}
}
}
</syntaxhighlight>
{{ out }}
<pre>
The first 32 Riordan numbers:
1 0 1 1
3 6 15 36
91 232 603 1585
4213 11298 30537 83097
227475 625992 1730787 4805595
13393689 37458330 105089229 295673994
834086421 2358641376 6684761125 18985057351
54022715451 154000562758 439742222071 1257643249140
The 1000th Riordan number has 472 digits
The 10000th Riordan number has 4765 digits
</pre>
=={{header|jq}}==
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